The present invention concerns the manufacture of tires. More particularly, it relates to the putting in place of the reinforcement cords of the tire, both to form the carcass thereof and to form the crown reinforcement, also known as the belt. As used herein, "manufacture of a tire" means complete manufacture, or else a partial manufacture comprising at least the reinforcements produced in accordance with the process to be explained, the manufactured tire, for instance, not necessarily progressing to the stage of forming a tread.
In this technical field, processes and machines are already known for making it possible to integrate the manufacture of the tire reinforcements in the assembling of the tire itself. This means that, rather than having recourse to semi-finished products, a reinforcement or reinforcements are produced in situ at the time that the tire is manufactured, and are produced from a single cord. There is already known, for instance, the solution described in U.S. Pat. No. 4,795,523 which requires the production of a large number of retaining hooks for the cord. There is also known the solution described in U.S. Pat. No. 4,952,259, which does not make it possible to produce carcass reinforcements in which the cord extends from one bead of the tire to the other. There is further known the solution described in U.S. Pat. No. 3,894,906 which could not be used either for the manufacture of carcass reinforcements and in which the means for applying the cord onto the support are incapable of operating at a sufficiently fast rate to assure satisfactory productivity.
The object of the present invention is to provide a process and apparatus for the manufacture of a reinforcement which are capable of producing both radial carcass plies and crown reinforcements constituting the triangulated belt in which the cords are arranged at an angle which may be as small as about 15.degree. and which does not employ hooks as provisional holding means. The term "cord" is used herein in a very broad sense, including a single cord or a cable or equivalent assembly, and this whatever the material constituting the cord.
In accordance with the invention, the process for the manufacture of a tire built progressively on a support by stacking the various components in the order and at the place required by the architecture of the tire in which the reinforcements of suitable material, for instance a natural or synthetic textile thread, a metal wire, a glass or other fiber or a mixed thread, are formed by advancing a given length of cord constituting a cord length over the support until at least the central part of said cord length is opposite its final position on the support is characterized by the fact that the said length is applied radially against the support by the action of two folders arranged on opposite sides of the support.
The specification describes and the drawings illustrate three embodiments of apparatus for the manufacture of a tire reinforcement employing this process, the first two being for the production of carcass reinforcements of rayon and the third for the production of crown reinforcements of steel. This will make it possible clearly to understand all aspects of the invention.
In accordance with the invention, the three embodiments of the apparatus have features in common comprising a displaceable rigid core, defining the shape of the inner surface of the tire, on which the tire is progressively built by stacking the various components in the order and at the place required by the final architecture of said tire, an assembly which permits the feeding of cord and the removal of a length of given size, which permits the insertion of said length in a device for the presenting of this length at the top of the core, the said presenting device placing at least the central or intermediate part of said length in a plane forming the desired angle with respect to the core just opposite its final place on the core, and of having two folders arranged on opposite sides of the core, each imparted a cyclic movement which approaches the core from the top thereof and descends in the direction towards the axis of rotation of the core, coming into contact with the length of cord and then moving towards the core during the course of the downward trajectory and applying the length of cord against the core at the desired place and then repeating the cycle with another cord.